NB-IoT Positioning Using Scheduled Reference Signal Measurements

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Narrowband Internet of Things (NB-IOT) devices face challenges with inaccurate positioning due to limited support for observed time difference of arrival (OTDOA) methods, require time synchronization among base stations, and have high power consumption, limiting their update rate and direct communication capabilities.

Innovation Solution

A method and system utilizing existing IoT devices as reference points, managed by a base station or location server, to perform RF measurements for positioning, with coordinated signal transmission and reception to enhance accuracy and reduce power consumption.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If OTDOA positioning method is used for NB-IOT devices, then positioning can be performed within the network, but positioning accuracy is insufficient and time synchronization among base stations is required

Engineering Contradiction:

Improvepositioning accuracyVSAvoidtime synchronization requirement

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent introduces a location server as an intermediary component that centralizes the synchronization and coordination functions. The location server receives positioning requests, selects appropriate reference devices, and manages the positioning process, thereby eliminating the need for complex distributed time synchronization among base stations while improving positioning accuracy through centralized control

Inventive Principle:

Principle #24Intermediary (Mediator)

2Measurement precision

If continuous power detection or transmission at higher rates is performed, then positioning accuracy can be improved, but power consumption increases

Engineering Contradiction:

Improvepositioning accuracyVSAvoidpower consumption

Core Design Contradiction:

Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The patent implements periodic positioning measurements instead of continuous power detection. The target device performs RF measurements at scheduled intervals based on positioning requests from the location server, and reference devices transmit reference signals periodically. This approach maintains sufficient positioning accuracy while significantly reducing power consumption compared to continuous operation

Inventive Principle:

Principle #19Periodic action

Solution Approach 2:

The patent enables the target device to autonomously perform RF measurements on expected reference signals using locally stored information about transmitting time and frequency allocation. The device can independently calculate its position without requiring continuous power detection or active transmission, thereby reducing power consumption while maintaining positioning capability

Inventive Principle:

Principle #25Self-service

3Reliability

If reference devices transmit signals continuously, then target device can always perform measurements, but power consumption of reference devices increases

Engineering Contradiction:

Improvesignal availabilityVSAvoidpower consumption of reference device

Core Design Contradiction:

ReliabilityVSUse of energy by stationary object

Solution Approach 1:

Reference devices transmit reference signals periodically rather than continuously. The location server schedules reference devices to transmit at specific time intervals based on positioning requirements. This periodic transmission ensures that signals are available when needed for measurements while significantly reducing the power consumption of reference devices compared to continuous transmission

Inventive Principle:

Principle #19Periodic action

Solution Approach 2:

The location server pre-configures reference devices with transmission schedules and parameters before positioning sessions. Reference devices are activated only when needed for specific positioning requests, allowing the system to maintain signal availability reliability while optimizing power consumption through advance planning and selective activation

Inventive Principle:

Principle #10Preliminary action

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Improves positioning accuracy and reduces power consumption by leveraging existing IoT devices as reference points, allowing for more precise determination of target device location without direct device-to-device communication.

Implementation Method 1

expecting a signal transmitted by the reference device and performing a radio frequency, RF, measurement by the use of the information, so as to obtain a measurement value dependent on a distance between the target device and the reference device

Methodology Applied

Scientific EffectRadio frequency measurement:

Data Source

PatentUS12621789B2Network assisted position measurements

Publication Date: 2026.05.05 FRAUNHOFER GESELLSCHAFT ZUR FORDERUNG DER ANGEWANDTEN FORSCHUNG EV

AI summary

A method for determining the position of a target device within a communication network is disclosed. A corresponding target device including a receiving unit and a radio frequency measurement unit, a base station or a location server including a selector and a transmitter, and to a reference device with configurable properties. A system including a base station or a location server, a target device, and a reference device for determining the position of a target device within a communication network are also disclosed.